Ohm's Law Calculator

Solve for any two unknown values in electrical circuits using Ohm's Law and the Power Law.

How to use this calculator

1. Select solve for.
2. Enter 2 known values.
3. Read all 4 variables.

Formula & method

Ohm's & Power Laws

V = I × R · P = V × I

Electrical circuit laws.

Example

2A across 10Ω = 20V and 40W.

Key insights

• V = I × R, P = V × I.

How to interpret your result

Power

Watts dissipated.

Frequently asked questions

Units?

V (Volts), A (Amps), Ω (Ohms), W (Watts).

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